In this application funds are requested to sponsor a chromosome 13 specific workshop. Chromosome 13 is 3.7% of the human genome and contains 100 megabases of DNA. Several genetic linkage maps of chromosome 13 have been constructed; the CEPH consortium map will contain over sixty loci with an average distance of less than 5 Cm. Highly informative PCR based markers are now being developed for this chromosome that will improve the genetic map and which will also be useful for constructing a physical map of this chromosome. Several somatic cell hybrids are available for this chromosome and a consensus panel was derived at HGM11 (London) which consisted of hybrids with evenly spaced breakpoints that are freely available. However, there will be a need to update this table by Sept 1992 due to the increase in both somatic cell and radiation hybrids. Until recently physical mapping on this chromosome had been limited to specific areas. Yeast artificial chromosome libraries are not available for this chromosome yet although several groups are involved in their construction. This workshop will consolidate information from many labs that will facilitate the mapping of this chromosome. This will include information on the characterization, source and availability of genetic markers, somatic cell hybrids, radiation hybrids, libraries (YACs, cosmids and phage), STS and CDNA. It should facilitate collaborations and foster more extensive scientific interchange. The workshop will last for two days in Dallas, Texas, and will consist of a series of short presentations on specific topics by each of the investigators involved, followed by an intense working session to resolve inconsistencies in the map, to produce consensus genetic and physical maps and a final consensus map and discussions on the characterization and a availability of molecular resources. In addition, the best method of exchanging information will be discussed. This workshop should determine the most efficient method for completing a detailed genetic and physical map of human chromosome 13. Relevant material generated at this meeting will be made available to the chromosome 13 committee.